1. Field of the Invention
The present invention relates to an optical switch adapted as an essential part in a WDM optical communication network, and more particularly to an apparatus for switching optical signals of multiple channels and a method for manufacturing the apparatus.
2. Description of the Related Art
Generally, an optical switch serves to change a route of an optical signal transmitted through an optical fiber in a Wavelength Division Multiplexing (hereinafter, referred to as “WDM”) optical communication network. The optical switch has been recently developed to employ a Micro Electro Mechanical System (hereinafter, referred to as “MEMS”) technique.
FIGS. 1a and 1b are schematic views respectively illustrating a structure and a switching operation of a conventional MEMS optical switch.
With reference to FIGS. 1a and 1b, the conventional MEMS optical switch employs a method in which light emitted from an input terminal optical fiber due to the displacement of an actuator having a MEMS structure is reflected by a micro mirror and then transmitted in at least two directions.
As shown in FIGS. 1a and 1b, the conventional MEMS optical switch comprises an input terminal optical fiber 11 to which an optical signal to be switched is inputted, a first output terminal optical fiber 12 arranged with the input terminal optical fiber 11 in a straight line, and a second output terminal fiber 13 arranged perpendicularly to the input terminal optical fiber 11. The conventional MEMS optical switch further comprises a micro mirror 14 located between the input terminal optical fiber 11 and the first and second output terminal optical fibers 12 and 13 for changing the direction of the inputted optical signal by means of reflection, and an actuator 15 for driving the micro mirror 14.
Hereinafter, a principle of the MEMS optical switch for switching the optical signal will be described in detail. As shown in FIG. 1a, the actuator 15 drives the micro mirror 14 such that the micro mirror 14 is moved to the opposite direction of the second output terminal optical fiber 13. Then, the optical signal inputted to the input terminal optical fiber 11 travels in parallel, and goes ahead through the first output terminal optical fiber 12.
On the other hand, as shown in FIG. 1b, the actuator 15 drives the micro mirror 14 such that the micro mirror 14 is moved to the direction of the second output terminal optical fiber 13 and located between the input terminal optical fiber 11 and the first and second output terminal optical fibers 12 and 13. Then, the optical signal inputted from the input terminal optical fiber 11 is reflected by the micro mirror 14 and goes ahead through the second output terminal optical fiber 13. The conventional MEMS optical switch switches the optical signal using the above principle, thereby having advantages such as an increased switching speed and a reduced rate of power consumption.
In order to process an optical signal with a large capacity so as to satisfy the rapid increase of subscribers of the optical communication network, a technique for providing signal-switching to multiple channels is required. However, the conventional MEMS optical switch using the micro mirror and the actuator has problems in that it is difficult to process the multiple channels due to characteristics of the optical signal and difficulty in packaging.